why not use digit separators everywhere?

Author: cor3ntin

clang/lib/Sema/SemaDeclCXX.cpp

@@ -13198,7 +13198,7 @@ NamedDecl *Sema::BuildUsingDeclaration(
     if (getLangOpts().CPlusPlus14 && II && II->isStr("gets") &&
         CurContext->isStdNamespace() &&
         isa<TranslationUnitDecl>(LookupContext) &&
-        PP.NeedsStdLibCxxWorkaroundBefore(20161221) &&
+        PP.NeedsStdLibCxxWorkaroundBefore(2016'12'21) &&
         getSourceManager().isInSystemHeader(UsingLoc))
       return nullptr;
     UsingValidatorCCC CCC(HasTypenameKeyword, IsInstantiation, SS.getScopeRep(),

clang/lib/Sema/SemaExceptionSpec.cpp

@@ -45,7 +45,7 @@ static const FunctionProtoType *GetUnderlyingFunction(QualType T)
 bool Sema::isLibstdcxxEagerExceptionSpecHack(const Declarator &D) {
   auto *RD = dyn_cast<CXXRecordDecl>(CurContext);
 
-  if (!getPreprocessor().NeedsStdLibCxxWorkaroundBefore(20160427))
+  if (!getPreprocessor().NeedsStdLibCxxWorkaroundBefore(2016'04'27))
     return false;
   // All the problem cases are member functions named "swap" within class
   // templates declared directly within namespace std or std::__debug or

clang/lib/Sema/SemaInit.cpp

@@ -645,7 +645,7 @@ ExprResult InitListChecker::PerformEmptyInit(SourceLocation Loc,
   if (!InitSeq && EmptyInitList &&
       InitSeq.getFailureKind() ==
           InitializationSequence::FK_ExplicitConstructor &&
-      SemaRef.getPreprocessor().NeedsStdLibCxxWorkaroundBefore(20140422)) {
+      SemaRef.getPreprocessor().NeedsStdLibCxxWorkaroundBefore(2014'04'22)) {
     OverloadCandidateSet::iterator Best;
     OverloadingResult O =
         InitSeq.getFailedCandidateSet()

clang/lib/Sema/SemaTemplate.cpp

@@ -4453,7 +4453,7 @@ static bool IsLibstdcxxStdFormatKind(Preprocessor &PP, VarDecl *Var) {
   // GCC master branch:
   // https://gcc.gnu.org/g:9361966d80f625c5accc25cbb439f0278dd8b278
   // https://gcc.gnu.org/g:c65725eccbabf3b9b5965f27fff2d3b9f6c75930
-  return PP.NeedsStdLibCxxWorkaroundBefore(20250520);
+  return PP.NeedsStdLibCxxWorkaroundBefore(2025'05'20);
 }
 } // end anonymous namespace
 

clang/lib/Sema/SemaTemplateInstantiateDecl.cpp

@@ -1449,7 +1449,7 @@ Decl *TemplateDeclInstantiator::InstantiateTypedefNameDecl(TypedefNameDecl *D,
   // happen to be processing that implementation, fake up the g++ ?:
   // semantics. See LWG issue 2141 for more information on the bug.  The bugs
   // are fixed in g++ and libstdc++ 4.9.0 (2014-04-22).
-  if (SemaRef.getPreprocessor().NeedsStdLibCxxWorkaroundBefore(20140422)) {
+  if (SemaRef.getPreprocessor().NeedsStdLibCxxWorkaroundBefore(2014'04'22)) {
     const DecltypeType *DT = DI->getType()->getAs<DecltypeType>();
     CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D->getDeclContext());
     if (DT && RD && isa<ConditionalOperator>(DT->getUnderlyingExpr()) &&